Fix clingo bootstrapping on rhel + ppc64le
Fix clingo bootstrapping on rhel + ppc64le

The system Python interpreter on rhel is patched to have
slightly different names for some architectures. This
makes it incompatible with manylinux generated extensions
for ppc64le.

To fix this issue when bootstrapping Spack we generate
on-the-fly symbolic links to the name expected by the
current interpreter if it differs from the default.

Links:
  https://github.com/pypa/manylinux/issues/687
  https://src.fedoraproject.org/fork/churchyard/rpms/python3/blame/00274-fix-arch-names.patch?identifier=test_email-mktime

LLNL/spack,LLNL/spack,LLNL/spack,LLNL/spack,LLNL/spack